Thermal electronics inspection reaching defect-free designs
>Xenics thermal cameras can detect heat defects in electronics before qualification, saving a considerable amount of time and money. The cameras can also be used for critical control of heat dissipation in a working instrument to optimize its lifecycle.
Thermal imaging in PCB prototyping and repair
The potential of thermal imaging for the development or repair of Printed Circuit Boards (PCBs) is still often underestimated. Early detection of Surface-Mount Technology (SMT) resistors running hot allows system engineers to re-size them before board qualification, saving a considerable amount of qualification time. A potentially very costly field repair can also be avoided in case long-term reliability problems would arise only many months later.
We will illustrate a successful customer case using the prototype PCB as shown in Figure 1.
The thermal image of the Gobi camera reveals three major hot spots after initial power-up of the PCB (Figure 2). At the top, leftmost (A) you can see a faulty logic Integrated Circuit (IC), probably damaged during production of the prototype. The two remaining hot spots (B and C) indicate small resistors getting too hot. After further investigation the customer learned that the resistors could operate too close to their maximum dissipation rating and chose other values.
The IC is responsible for auxiliary signal generation, and its failure is not obvious from a system perspective. Quick identification of a failing IC with our Gobi thermal imaging camera saved the customer precious debugging time.
Thermal imaging in power electronics motor drives
Electronic motor controls use Insulated Gate Bipolar Transistors (IGBTs) to control current in the electric motor windings. Sophisticated motor control algorithms ensure the drive’s excellent speed and position accuracy as well as efficiency. A single IGBT chip capable of carrying more than 100 A must be capable of dissipating more than 200 W, but weighs not more than 1 gram. Verification of the thermal design using a Gobi thermal imaging camera is therefore essential.